Set owner and status when creating or updating issues.

owner => The username of the uploader
status => Started
Keep track of the google code issue number.
Update issue immediately after creation to set the owner.

Apparently, the google code API refuses to set the owner
upon issue creation, but we can set it by issuing an
empty comment.
Display google code issue number in git-cl status.
Post the short patchset description at the google issue tracker.
Typos and formatting of message.
Refactor how git-cl sets the owner.

This way non-members don't get a Traceback.
Avoid a couple of mistakes in handling google issue numers.

- Protect against unsetting IssueId when it is already unset.

- The google issue_id can be either a str or an int object.
Return the google issue_id even if changing issue labels failed.
Avoid confusing Rietveld/Tracker issue mess.
Merge pull request #1 from jrioux/issue-handling

Issue handling
Fix https change with google update
Include binary data in diffs.
Update to use https for Rietveld.
Convince git-cl that images are binary.
Merge pull request #2 from jrioux/rietveld

Rietveld patches

Include binary data in the patch upload to Rietveld.

This works with both "git cl patch X" and "test-patches" aka Patchy.
Tested this myself with https://codereview.appspot.com/13054043/

Also update to use https.